Replace ProximityAuthUIDelegate with ProximityAuthClient.

components/proximity_auth/webui/proximity_auth_ui.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_PROXIMITY_AUTH_WEBUI_PROXIMITY_AUTH_UI_H_
 #define COMPONENTS_PROXIMITY_AUTH_WEBUI_PROXIMITY_AUTH_UI_H_
 
 #include <string>
 
 #include "content/public/browser/web_ui_controller.h"
 
 namespace proximity_auth {
 
-class ProximityAuthUIDelegate;
+class ProximityAuthClient;
 
 // The WebUI controller for chrome://proximity-auth.
 class ProximityAuthUI : public content::WebUIController {
  public:
   // Note: |web_ui| and |delegate| are not owned by this instance and must
   // outlive this instance.
-  ProximityAuthUI(content::WebUI* web_ui, ProximityAuthUIDelegate* delegate);
+  ProximityAuthUI(content::WebUI* web_ui, ProximityAuthClient* delegate);
   ~ProximityAuthUI() override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ProximityAuthUI);
 };
 
 }  // namespace proximity_auth
 
 #endif  // COMPONENTS_PROXIMITY_AUTH_WEBUI_PROXIMITY_AUTH_UI_H_